The present invention relates to a clip for surgical procedures, for example, for aiding consolidation or osteosynthesis between bone parts wherein it is necessary to maintain the parts together for the duration of the process of union between them. Furthermore, the present invention also permits two parts of a bone to consolidate properly, correcting any tendency towards malformation thereof. In addition, the clip of the present invention allows ligaments or tendons to be connected to bone parts. More particularly, the present invention relates to a surgical clip that has elastic properties or that is deformable to set the clip in place.
Various devices are known which permit the osteosynthesis of two bone parts or fragments by holding them together and avoiding their movement insofar as possible. Thus, there are external elements such as casts and internal elements such as screws, plates, clips, etc. which perform this function. Argentine Patent 203,977 refers to a curved nail for the treatment of fractures and comprises an elongated body which at one end has a coupling part which is to be inserted into the bone. Types of plates and nails for knitting of femur heads are known from Argentine Patent 212,889 and Argentine Patent 214,240. Connecting plates for two fragments of bones are also known from Argentine Patent 211,803 in which a plate with orifices for screws is placed over the parts to be connected.
Argentine Patent No. 236,884 refers to a fastening clip especially for osteosynthesis and, for its application, the clip must be inserted in the bone by at least one pair of legs while a bridge portion which connects the two legs together remains outside the bone and effects the connection between the two bone fragments. This clip is to be used especially together with a similar clip, each one placed on each adjacent portion of bone to be connected; the bridge portions of the two clips are then connected together by an elastic element which pulls the two bone parts together that are being united.
Applicant's U.S. Pat. No. 5,449,359 discloses an elastic clip for osteosynthesis which is constructed by welding together a plurality of staples. The clip, in one embodiment, has two bridge sections between legs, the bridge sections being separated by a gap. An instrument is inserted into the gap to widen the gap which causes the legs of the clip to move together thereby causing the bone fragments in which the respective legs are inserted to move together.
However, the clip of the above-identified U.S. Patent suffers from the disadvantage that it is made, in the embodiments illustrated in that patent, in a plurality of pieces, thus increasing cost.
Other devices are also known for securing soft tissue, e.g., tendons and ligaments to bone. The tendons or ligaments have to be fastened to the bone through a device that provides enough stability in order to be able to start the rehabilitation treatment as fast as possible. That has been shown in knee surgery; the new fixation systems for surgery of the cruciate ligaments are very strong. There is no need for a plaster cast immobilization, a knee brace is sufficient, and it is removed partially very early to begin motion of the joint, because it has been shown that the motion improves the healing of the tendons or ligaments.
The known devices for soft tissue fixation that are used are:
1) Interference screws, in which a ligament or a tendon is submerged in a hole in the bone, and a screw is applied in that hole. The threads fix the tendon to the wall of the hole. The disadvantage is that when one rotates the screw, the tendon is also rotated, and it can also cut the tendon fibers if the fit is too tight.
2) Screw with a washer with spikes, in which the tightening of the screw drives the spikes from the washer through the tendon fibers, pressing them against the bone. The disadvantage of this system is that the tendon is unevenly pressed, tilting the washer.
3) Anchor, in which a device with two prongs at the end is provided. The other end has two sutures to tie the tendon, which is the weak point of the system.
Although some of the known devices have given generally good results, the surgeon is confronted with the problem that some prior art connecting elements are bulky and complicated which increases the traumatic suffering to which the patient is subjected. Some of the smaller ones, like clips, do not succeed in efficiently fastening the bone portions or tissue members together, because it is not possible to avoid shifting or turning of the bone parts or tissue members with respect to each other. When it is desired to consolidate two bone fragments, it is necessary to have excellent contact between the parts as well as compression between bone ends. Scientific investigations have shown that by suitable compression between the parts to be connected, a faster consolidation of better quality is obtained.
Since it is necessary to work through the wound of the patient in order to place the parts to be connected in contact and fix them, it is preferred that the connecting means be as simple as possible. It is also preferred that the connecting elements be as simple as possible to fix in position, and require as little time as possible to set, in order to minimize trauma.
In the prior art, there are simple clips of U-shape which are very similar to those clips which are used in paper staplers. These U-shaped clips have sharpened ends which are inserted in a bone portion and they maintain their position by the rigid structure of the legs of the U-shape. However, these conventional clips maintain the same distance between the bone fragments and, therefore, if there is not coaptation, there is instability in rotation, which means that the bone portions may turn with respect to each other and may even separate. This phenomenon would not occur if one succeeded in maintaining the bone ends compressed against each other.
In the contrary case, in which it is desired to maintain a degree of separation between the bone fragments, which case is particularly useful for bone malformation correction, there are no clips known to applicant, other than applicant's clip described in U.S. Pat. No. 5,449,359, which make it possible to obtain this spacing, and therefore, it would be very useful to have clips which make it possible to achieve this at reduced cost. The clip of U.S Pat. No. 5,449,259 can achieve this but it is desirable to improve on that clip by providing such a clip of reduced cost.
As stated above, the aim of attaining a desired spacing between bone fragments could be obtained with connecting elements such as plates and screws, but these are much bulkier, require major surgical procedures for the placing thereof and the possibility of trauma is increased.
In addition to the surgical use of the invention, it is also possible to use the invention in non-surgical areas, e.g., construction, woodworking, the general fastener industry, etc.